Flooding question

We are in the process of making a refugium filter for our new tank. What can be done to stop flooding the refugium if we lose our electric ? Has this happened to anyone....

 

How are you setting it up?

 

We have a 90 gallon tank with a 30 gallon refugium under the cabinet.

 

Okay, is the tank drilled or are you using a hang on back overflow box?

 

it's drilled on the bottom.

 

make sure you have siphon breaks drilled into your outlets from your overflows... (a small hole just below the waterline in your display tank in the outlets) shut off your pumps... let the water drain till the siphon breaks stop the flow back into your sump.. now, add water to your sump to a comfortable level... (I would say no more than a couple inches from the top of the sump tank) this is the level the water will rise in the sump in the event of a power outage.. then turn your pumps on.... I am stating this assuming you have some kind of overflow box or standpipe on your bulkhead that is drilled in the bottom... if you don't already have that..... you will need to get one or the other, or both!

 

When the power goes out, the sump will fill up with any water that's left in the main tank above the level of the overflow/s. If you have too much water in the sump, the sump will overflow. So the trick is to leave enough space in the sump to compensate for the extra water during a power outage. This will vary tank by tank. Sometimes you'll only need to leave a few inches of space at the top. Sometimes you'll need to leave 6 or more. You'll need to do a few "practice" runs where you turn off the return pump and let the main tank drain into the sump. Bail water from the sump if the water level gets too high. When you get to the point where the main tank stops draining into it, and the sump is not overflowing, you know that this is the safe level where there's enough space in the sump to hold any extra water during a power outage. When you turn the return pump back on, keep the water at this level, and mark it with a sharpie so that you know not to go above that water level.

You will also need to have a one way valve in your return line or small holes drilled in your return line output to prevent a back siphon from draining your main tank in a power outage.

 

Doh! Ninja'd!

 

OK, I should of told you I'm a newbie at this. I've had a 46 gallon FOWLR for a year. It has a canister filter. So, this refugium is all new to me. If I keep the return close to the top of the water, would that be OK for it not going back in to the refugium ? I don't understand the drilling holes thing. I would post a pic, but we are still making the refugium. It's not all hooked up yet. I was just thinking about the backing up thing last night. Thank you for your patients......